docs: def form_valid(self, form):
          '''
          Create slots and return success message.
          '''
          startDate = form.cleaned_data['startDate']
          endDate = form.cleaned_data['endDate']
          startTime = form.cleaned_data['startTime']
          endTime = form.cleaned_data['endTime']
          instructor = form.cleaned_data['instructorId']
  
          interval_minutes = getConstant('privateLessons__lessonLengthInterval')
  
          this_date = startDate
          while this_date <= endDate:
              this_time = startTime
              while this_time < endTime:
                  InstructorAvailabilitySlot.objects.create(
                      instructor=instructor,
                      startTime=ensure_localtime(datetime.combine(this_date, this_time)),
                      duration=interval_minutes,
                      location=form.cleaned_data.get('location'),
                      room=form.cleaned_data.get('room'),
                      pricingTier=form.cleaned_data.get('pricingTier'),
                  )
                  this_time = (ensure_localtime(datetime.combine(this_date, this_time)) + timedelta(minutes=interval_minutes)).time()
              this_date += timedelta(days=1)
  
          return JsonResponse({'valid': True})